Table 1 Demographic and clinical features of axial SpA patients included in the RBE
Characteristic | Total population (n = 1096) | HLA-B27 positive (n = 805) | HLA-B27 negative (n = 291) | p Value |
|---|---|---|---|---|
Male gender (n, %) | 803 (73.3) | 609 (75.7) | 194 (66.7) | 0.004 |
Disease duration (years, SD) | 18.3 (12.0) | 18.6 (12.5) | 17.4 (10.8) | 0.485 |
Mean age at symptoms onset (years, SD) | 28.4 (12.0) | 27.0 (11.6) | 32.2 (12.2) | < 0.001 |
Mean age at diagnosis (years, SD) | 34.2 (12.4) | 32.7 (11.7) | 38.1 (12.5) | < 0.001 |
Mean delay in diagnosis (years, SD) | 9.1 (9.3) | 9.1 (9.7) | 9.3 (8.4) | 0.284 |
Race (self-reported skin color) | 0.121 | |||
White (n, %) | 537 (50.9) | 412 (53.0) | 125 (44.8) | |
Black (n, %) | 76 (7.2) | 52 (6.7) | 24 (8.6) | |
Brown (Pardos) (n, %) | 387 (36.6) | 271 (34.9) | 116 (41.6) | |
Yellow (Asian Brazilians) (n, %) | 38 (3.6) | 30 (3.9) | 8 (2.9) | |
Indigenous (n, %) | 18 (1.7) | 12 (1.5) | 6 (2.2) | |
BMI (mean, SD) | 26.5 (4.8) | 26.4 (4.6) | 26.8 (5.2) | 0.493 |
Family history of SpA (n, %) | 109 (22.1) | 86 (24.7) | 23 (15.8) | 0.032 |
EMMs | < 0.001 | |||
Any (n, %) | 231 (34.8) | 170 (35.4) | 61 (33.3) | |
Psoriasis (n, %) | 39 (5.9) | 15 (3.1) | 24 (13.1) | |
IBD (n, %) | 30 (4.5) | 14 (2.9) | 16 (8.7) | |
Uveitis (n, %) | 176 (26.5) | 147 (30.6) | 29 (15.8) | |
Painful enthesis count (mean, SD) | 5.0 (4.7) | 5.0 (4.8) | 5.1 (4.5) | 0.554 |
Painful joint count (mean, SD) | 6.9 (10.5) | 5.7 (8.7) | 9.8 (13.5) | 0.007 |
Swollen joint count (mean, SD) | 3.6 (4.2) | 3.3 (4.0) | 4.3 (4.5) | 0.24 |
BASDAI (mean, SD) | 4.1 (2.5) | 4.0 (2.5) | 4.3 (2.4) | 0.019 |
ASDAS-CRP (mean, SD) | 3.4 (1.7) | 3.3 (1.7) | 3.7 (1.8) | 0.004 |
ASQoL (mean, SD) | 7.5 (5.6) | 7.3 (5.7) | 8.1 (5.4) | 0.034 |
BASMI (mean, SD) | 3.9 (2.1) | 3.8 (2.1) | 4.2 (2.1) | 0.045 |
BASFI (mean, SD) | 4.6 (2.9) | 4.5 (2.9) | 4.8 (2.8) | 0.059 |